Strong and binder free structured zeolite sorbents with very high CO2-over-N2 selectivities and high capacities to adsorb CO2 rapidly
Strong and binder free structured zeolite sorbents with very high CO2-over-N2 selectivities and high capacities to adsorb CO2 rapidly
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DOI：
10.1039/c2ee21153j
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发表时间：
2012-06-01
影响因子：
32.5
通讯作者：
Bergstrom, Lennart
中科院分区：
文献类型：
--
作者：
Akhtar, Farid;Liu, Qingling;Bergstrom, Lennart
机械强度高的沸石纳卡整料与层次的孔显示非常高的CO2-过-N-2的选择性。通过脉冲电流处理（PCP）生产沸石整料，而不使用添加的粘合剂并且具有保留的微孔晶体结构。测定了CO2和N2-的吸附等温线，并利用理想吸附溶液理论（IAST）预测了CO2和N2-的共吸附。IAST预测表明，纳卡的整体式吸附剂可以在具有类似于烟道气的组成的二元混合物（在25 ℃和101 kPa下15 mol% CO2和85 mol% N2）中达到非常高的CO2对N2的选择性。K+含量为9.9at%的结构化纳卡整料将>1100的CO2相对于N-2的选择性与高CO2吸附容量（4 mmol g（-1））和快速吸附动力学（大约1分钟）结合。基于IAST CO2相对于N-2的选择性和时间依赖性CO2吸收能力的品质因数（F）的估计表明，具有9.9at%的K+含量的PCP产生的结构化纳卡提供远上级13 X吸附剂的性能，特别是在短循环时间下。
Mechanically strong monoliths of zeolite NaKA with a hierarchy of pores displayed very high CO2-over-N-2 selectivity. The zeolite monoliths were produced by pulsed current processing (PCP) without the use of added binders and with a preserved microporous crystal structure. Adsorption isotherms of CO2 and N-2 were determined and used to predict the co-adsorption of CO2 and N-2 using ideal adsorbed solution theory (IAST). The IAST predictions showed that monolithic adsorbents of NaKA could reach an extraordinarily high CO2-over-N-2 selectivity in a binary mixture with a composition similar to flue gas (15 mol% CO2 and 85 mol% N2 at 25 degrees C and 101 kPa). Structured NaKA monoliths with a K+ content of 9.9 at% combined a CO2-over-N-2 selectivity of >1100 with a high CO2 adsorption capacity (4 mmol g(-1)) and a fast adsorption kinetics (on the order of one minute). Estimates of a figure of merit (F) based on IAST CO2-over-N-2 selectivity, and time-dependent CO2 uptake capacity, suggest that PCP-produced structured NaKA with a K+ content of 9.9 at% offers a performance far superior to 13X adsorbents, in particular at short cycle times.